/*
The external control pin is used to set the loudness volume parameter for the algorithm. This should be a 5.23 value between 0.0 and 1.0 which represents the desired volume (for example 0.5 for a level of -6dB). This controls the output volume of the entire block, and more importantly, it is also sets the threshold for the loudness algorithm. At low levels, the loudness algorithm boosts the low frequencies somewhat more than it does the high frequencies. For a control input of 1.0 (0dB), no matter what the input level is, there is no boost, LF or HF (See the Loundess (Low and High) level slider as it performs a similar function).
*/
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